Whatever your chosen profession, we all have something in common: We're trying to do the best we can in our careers. Of course we aren't going to gossip about our boss, fail to meet our deadlines, or do anything else to jeopardize our jobs or careers… knowingly.

It's that "knowingly" that's the problem. We can easily avoid the professional pitfalls we know, but what about the ones we don't? And even more important, could we be making major mistakes when we think we're making the right move? To keep from falling into that trap, we asked career experts to shed light on the missteps we make without even realizing, whether at the office or in the trenches of a job hunt. Are you making these mistakes?

Keeping Yourself Offline

Knowing that social media channels such as Twitter, Facebook and even LinkedIn are rife with opportunity for career-damaging blunders, it's understandable that you might want to lay low, leave your profiles dormant or even take yourself offline entirely.

But that's the wrong move, according to Cheryl Palmer, certified career coach and owner of Call to Career. "According to recent data, the majority of recruiters now scour online sources for additional information on candidates," says Palmer. "Positive online information about you will improve your job prospects, since that is what recruiters will be looking for to determine who they call for an interview." She points out that since social media sites such as LinkedIn, Twitter and Facebook are some of the first results that show up on search engines, you'll want to be represented—and represented well.

It's pretty common knowledge that potential employers may check your social media accounts.…
Read more Read more

Palmer says that just having the profiles isn't enough—you must have a dynamic presence. That means using these channels to promote yourself in a positive, professional way. Worked on a new ad campaign? Tweet it. Added to your photography portfolio? Facebook it. Come across a fascinating industry article? Share it on LinkedIn. When recruiters or interviewers look you up, they'll find an engaging, productive individual.

Dear Lifehacker, On every job application, companies ask me for my LinkedIn profile. The problem…
Read more Read more

(And if managing multiple networks seems like too much, you can always automatically link your Twitter, Facebook, and LinkedIn, so every post broadcasts to all three networks. Don't worry, we won't tell the recruiters.)

Bonding With Co-Workers

You're right: It's always a good idea to attend work happy hours, volunteer days, and other forms of group bonding, because while these people are your colleagues, they're also the people with whom you spend 40-plus hours a week.

But bonding becomes problematic when you become very close to some co-workers … and not others. "It's a mistake to align yourself with one person or one camp," cautions Marian Their, founder and C.E.O. of coaching, training and consulting firm Expanding Thought. "While it's tempting to align yourself with a strong person or group, in doing so, you separate yourself from everyone else. Then what happens when personnel changes occur, someone falls out of favor, or you need support from someone not in the chosen group?"

To keep from getting in too deep with some colleaguesover others, Their advises people to take some simple steps to keep things friendly across the board: Go to lunch with a group of people, or different people each day; sit next to people who aren't your deskmates already at meetings; mix up your routine a bit—stop by the kitchen or watercooler for a brief chat at different times of day, to run into different people.

Everyone knows what it's like to have a frustratingly dumb coworker to deal with, but what if…
Read more Read more

"The higher up in the organization you go," reminds Their, "the more important it is to be observant and prudent. Remember that while having allies is extremely important, so is having people who will challenge you."

Championing Make-Ends-Meet Jobs

We don't need to tell you that there's no shame in taking a gig unrelated to your ultimate career path (think: waiting tables) to make ends meet while hunting for other opportunities, or to make a little extra money on the side. Plus, your scrappiness will show future employers that you're hardworking and ready to hustle, right? Not exactly.

"As a job hunter, you should be looking at yourself as a candidate through your potential employer's eyes," advises Robert Meier, president of Job Market Experts. "And to an employer, a side job is a distraction from your primary position. A Fortune 500 company simply isn't going to appreciate your time as a night manager at 7-11."

Instead of trying to bulk up temporary jobs by explaining how they taught you "tenacity" and "reliability," Meier recommends minimizing such positions down to only a line on your résumé—or eliminating them altogether while bulking up your more relevant past positions. "The only time you should include a job like this on your résumé is if it furthers your career objective," he says. For instance, a job on the sales floor in a clothing chain may be valuable if you're applying to be a buyer for J.Crew; your time as a fitness instructor may be relevant if you're applying for an operations position at Under Armour.

There are a lot of important things you should put on your resumé, but just important are the…
Read more Read more

If you spent six months scooping ice cream and are now applying for a completely unrelated corporate job in ad sales, Meier recommends eliminating your make-ends-meet job from your résumé altogether. If your employment gap should come up in an interview, he says, explain that you were devoting your full attention to finding the right job in a difficult economy—an understandable excuse if it's been 12 months or less.

Relying on a Pros and Cons List

Raise your hand if you've ever made a pros and cons list about a potential job or project. It's the sensible move—you're laying out all the reasons you should and shouldn't take on a new venture in order to make an informed, rational decision.

But informed and rational isn't all it's cracked up to be. "If you are getting a bad gut feeling about working for a certain boss, a 'pit in the stomach' sensation about a dicey work environment, or are self-rationalizing over taking a major pay cut, you should never ignore the little voice in your ear warning you that something is wrong," explains Cheryl Rich Heisler, founder and president of career-consulting site Lawternatives.

If you're getting a bad feeling about an opportunity that seems promising on the surface, says Heisler, it's time to get more information. "Dig deeper, and either reassure yourself that your impressions are wrong, or back away from the offer. This is true even for choosing your first career track—trust yourself." That's not to say that a few nerves means you should bail on a second-round interview, but if you can't shake your anxiety and can't alleviate it with more information, it might be time to take a step back.

"If," says Heisler, "after doing your research and networking, the career, industry or job you're exploring doesn't feel right to you, reconsider. The happiest employees are working in areas they enjoy within industries they love."

Being Perpetually Available

Chances are, your current employer values face time—that is, how much time you're in the office, working away at your desk. And when you aren't face-to-face, you're accessible by phone, email, text, or carrier pigeon, whether it's midnight, midnight on Saturday, or midnight on Saturday during your vacation.

"When you're refusing to delegate responsibilities it shows that you aren't a teacher or mentor, and certainly not a supervisor, which is criteria for promotion," says Bruce Hurwitz, executive recruiter and author of "Success! As Employee or Entrepreneur." And when you don't take vacation, he says, it can create an air of superiority—like you feel nothing can get done without you.

There are a lot of great tutorials on interviewing for jobs, negotiating a raise, and angling for a …
Read more Read more

"People make the mistake of being too available because they don't know how to say no,'" says Hurwitz. "They think the person they are rejecting will be mad at them, and it will affect their relationship." But, he adds, this isn't necessarily the case. If you're perpetually available and looking to break the cycle, Hurwitz recommends starting with a "conditional yes," where, upon hearing about a new assignment, you reply, "I'd be happy to. Just let me get this job done, and if you still need my help, I'm there for you."

Of course, no one is recommending you skip out on your work, and it's likely that there will be occasions you'll have to be available outside the office. But delegating tasks to be completed without your direct oversight, or even in your absence, is a skill every manager—or would-be manager—should have.

Libby Kane is the associate editor at LearnVest. After graduating from Wellesley College, where she was an editor at the Wellesley News, she joined the LearnVest team. Her work has appeared on the Huffington Post, Forbes, the Fiscal Times and more. Libby spends her time visiting the best museums she can find—the mustier, the better. Follow Libby Kane on Twitter and Google+

LearnVest empowers everyone to take control of their personal finances. They provide expert advice and resources, and financial plans that fit your budget.